Five Learnings From Running 100 Miles

July 27, 2023

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Notes on Drive: The Surprising Truth About What Motivates Us

August 09, 2022

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Strength Workout

July 16, 2022

A simple workout focused on injury prevention

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2022 Readings

April 14, 2022

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Visualizing Personal Finances with Matplotlib

March 27, 2022

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2021 Readings

May 09, 2021

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New Year Goals

January 10, 2021

Small goals for the new years

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Building An Analytics Stack In 2020

March 29, 2020

What I learned building analytics from scratch

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H1 Readings

July 03, 2019

Max Levchin, Founder & CEO of Affirm, on How HVF (Hard, Valuable, Fun) Has Guided His Founder Journey

Q1 Book List

March 31, 2019

  • Titan: The Life of John D. Rockefeller, Sr., Ron Chernow
  • Testosterone, Joe Herbert
  • A Bridge Too Far, Cornelius Ryan
  • The Storm Before the Storm: The Beginning of the End of the Roman Republic, Mike Duncan

Blog Post On Active Learning

March 15, 2019

I wrote a short blog post for Coalition: Improving Cyber Underwriting With Active Learning

Price Optimization With Adverse Selection

February 11, 2019

The difference between pricing insurance and pricing bananas

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X Financial Releases F 1

September 17, 2018

Also, a book probably worth reading:

Microbrands Take Over

September 13, 2018

These days my Instagram feed feels more like QVC than a social network

Terrible Graph O The Day

July 31, 2018

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Venmo removes browser payments - and you should too

July 16, 2018

Why more financial systems should kill website functionality

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Stock Options and the Lying Liars Who Don't Want to Expense Them

July 03, 2018

Still rings true, still not expensed


Wrap Statsmodels In Sklearn

May 21, 2018

How to use sklearn cross-validation on a statsmodel formula-style model

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Fraud False Positives In Wsj

April 19, 2018

Why Paying For Fast Shipping Could Get You Flagged As a Fraudster

Must have been a slow newsday

2018 Race Schedule Up

January 22, 2018

2018 Race Schedule

Community Reinvestment Act Under Revision

January 10, 2018

A recent WSJ Article reports that the Trump administration is planning on revamping the 1977 Community Reinvestment Act (CRA), which requires banks to serve low-and-moderate income (LMI) neighborhoods and be evaluated for compliance. You can search the CRA ratings history of any bank here.

One of the inputs is the number of physical branches in LMI income census tracts. The WSJ suggested that this has led banks to open branches in financial district/downtown areas, which often are classified as LMI but have very few residents (article: Never Mind the Ferrari Showroom, Bank Regulators Say This Is A Poor Neighborhood). A tract in downtown San Francisco, for example, had 53 bank branches in a LMI tract with less than 2,000 total residents. These branches are probably not primarily serving LMI residents, but instead, office workers that live in other neighborhoods and use the downtown branches during the workday.

This is an interesting examples of well-intentioned but ultimately perverse incentives in regulation and I’m excited to see the proposed changes.

Thaler Wins Nobel For Behavioral Econ

October 09, 2017

Prospect theory contains four main elements.

First, individuals derive utility not from wealth (or consumption) levels, but rather from gains and losses relative to some reference point.

Second, individuals are more sensitive to losses than to gains, i.e., they exhibit loss aversion. The utility function captures the loss aversion of individuals in a kink at the reference point, with the function being steeper in the losses region compared to the gains region.

Third, individuals exhibit diminishing sensitivity to gains and losses, i.e., moving from a $100 to a $200 gain (or loss) has a larger utility impact than moving from a $10,100 to a $10,200 gain (or loss).

Fourth, the theory incorporates probability weighting: individuals weigh outcomes by subjective, transformed probabilities or decision weights, overweighting low probabilities and underweighting high probabilities.

Prize Announcement and Research Summary

Send Your Google Cal Availability Quick

July 14, 2017

Someone asks you for your availability. You don’t want to share with them your calendar details or work through gmail’s menu of shared calendar settings.

Fire up the javascript console from within chrome and hit it:

function replaceText(selector) {
  var elems = document.getElementsByClassName(selector), i;
  for (i = 0; i < elems.length; i++)
      elems[i].innerHTML = 'busy';

//some type of google cal span

//another type of google cal span

//location details

Styrofoam Cup Training

July 01, 2017

Successful training is exactly like turning a Styrofoam cup inside out. So long as you take it slowly, you’ll be able to do it. Try to rush things and you’ll tear the cup. You are the cup.

  • Going Long, Joe Friel & Gordon Byrn

Q2 Articles To Read

June 27, 2017

Online Lender Rates Comparison

June 22, 2017

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Q4 Articles Worth Reading

October 06, 2016

CB: Let’s talk about Math. What are statistical skills that any data-driven person should be comfortable with?

LK: Basic regression techniques are widely used but poorly understood. You need to know when assumptions break down and how to interpret results accurately. Difference in differences, instrumental variables, and discontinuity analysis are commonplace tools with a lot of applied value.


vim anti-patterns

Kalman filter explanation

Analyze your email with python

The prevalence of statistical reporting errors in psychology

Text analysis of Trump’s tweets confirms he writes only the (angrier) Android half

Using Collections On A Jekyll Blog

September 15, 2016

Here's how I recently moved all of my race information from a hardcoded html table to jekyll’s built-in collection feature

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Payments And Pricing

August 18, 2016

Some interesting readings.

Gunung Kerinci Ascent

January 01, 2016

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Dplyr Stack Overflow

November 01, 2015

I joined stack overflows and answered a couple of dplyr-related questions. My favorite one involved twisting eval(parse()) to apply generic ANOVA’s to grouped data.

  1. My favorite: Apply anova over subsets of data

  2. Connect to database with stored credentials in dplyr

  3. Connect to an external server’s database

If you’re a SO (or dplyr) veteran, let me know what I can do better!

R With Amazon Redshift

October 01, 2015

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Analyzing Negotiation Genius

May 29, 2015

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New Site Style Soon

May 05, 2015

I’m going to update the css of my site. I wrote this in college and it looked cool in 2010 when I didn’t know any CSS. Now it doesn’t look good so I will change it.

Contributing To R Graphics Gallery

May 05, 2015

I recently put out a pull request for romain francois’ long defunct R Graphics Gallery, which used to be an awesome site! Hopefully it will be accepted. Check it out at github

Correlated Regressors and R Markdown

May 02, 2015

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Halloween Magic With Functionals

October 30, 2014

Happy Halloween! This post explores the trendy %>% operator to add aspects of functional programming to R.

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Dplyr And Datatable

October 07, 2014

Working with very smart people from other schools has been great for improving R skills, and for better understanding the ones (I thought) I already knew.

A common task is the classic Split-Apply-Combine formula, whereby a dataset is broken into chunks (perhaps country-wide data broken into states) then an operation is performed (e.g. the standard deviation of earnings data in each state), and then the results put back together into a table.

I used to perform these operations with plyr. I now use dplyr, its faster, newer relative that is specialized for data frames. Also used in the office is data.table, which has been shown to be faster, as of April 2014. A serious back-and-forth between the two amazingly talented creators of the packages can be found here.

Why do I use dplyr instead of the slightly faster data.table? A good overview can be found at ZevRoss, but the recent merge of syntax in dplyr and magrittr to use %>% as a common pipe operator means that functional programming is here to stay.

The best tutorial of dplyr comes straight from Hadley’s dropbox and includes references to Allie Brosh’s Hyperbole and a Half and also an interesting diagram of where dplyr fits in with the rest of Hadley’s packages.

…Now, back to parallelization

Data Science at Imperial College, London

August 03, 2014

I’ll be spending August at the Data Science institute of Imperial College, London. They have collaberative corporate relationships with companies like Huawei and KPMG. I’m not sure if Universities in the US are as adept and collaberating with the private sector (for better or for worse, I don’t know). I’ll be working on an interactive visualization for the Supercomputing conference this November.

Hiking trip in Montana

July 07, 2014

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Hackathon in Amsterdam

June 24, 2014

I had the opportunity to attend this year’s Open Science Data Cloud (OSDC) conference, at the University of Amsterdam.

OSDC is a cloud hosting organization for open science (duh) They provide academic researchers with a secure, dedicated compute cloud and have interesting projects in biology and geospatial analysis. They also push for reproducible research in academia, which is a critical need. (link to picketty)

The conference ended with a casual hackathon contest, judged by professors and post-docs from several universities.

My partner and I, Cody Buntain, won 1st place for Mayfly a series of bash scripts that installs dropbox on a computer and uploads the contents of a directory to a custom folder and then returning a public-viewing link.

We hope to make it easier for people to begin reproducible research by making it dead-simple to share your code and output with collaberators. Surely, I thought, there must be a middle ground between emailing out large code files (which some professors do) and learning knitr (which most professors don’t). With Mayfly, the dropbox folder always contains the most up-to-date code. For programs like knitr, dropbox’s ability to view html files online means that results are viewable without downloading anything!

Knitr and git and all of these “cutting edge” (at least in academia) tools are great, but what’s the point if only 5% of professors use them? Expanding the use of reproducible research is perhaps more important than increasing its sophistication.

Data Vizualization Challenge

June 10, 2014

I’m very honored to have been awarded first place in UChicago’s Data Visualization Challenge for “Making Indonesia”, a website with a series of graphs and an interactive visualization exploring Indonesia’s manufacturing sector. You can explore the website here.

My favorite entry of the competition was Kevin Wang’s Can I graduate.

Zero To Windows 8.1 In Ten Minutes

May 23, 2014

After hearing many friends express frusturation with windows 8.1, I wrote a short guide to help restore producity (and perhaps sanity), as well as learn something new

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Text Analysis Research

May 13, 2014

A short presentation on text analysis

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Cannot Find Vcvarsall

May 03, 2014

A fix for a common windows python error

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Evaluating Chicago's Violence Reduction Initiative

March 10, 2014

A paper I co-wrote with a classmate on Chicago's controversial (and expensive) Violence Reduction Initiative has been published in the Nottingham Economic Review

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R: Love, Money & Bitcoins

February 15, 2014

My favorite articles from the past month

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Fun with Ctypes

February 03, 2014

So this is what I'm up to these days:

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Come and run the Chicago Spring half marathon!

February 02, 2014

I’ve signed up to run my second Chicago Spring Half Marathon. I ran it last year with a group from UChicago Road Runner. The race is a ton of fun, and I’m trying to beat my previous time. Sign up here $70, (includes a great brunch, very good support stations) and come run with us!

New Year, New Website

January 02, 2014

I’ve rewritten my site using Jekyll, and hosting it on my own domain, as opposed to the University-provided home page. It’ll be, at worst, a fun experiment! The old website, which is honestly better looking, can be found here

Enova Data Competition

October 15, 2013

I was awarded 1st place, along with teammate Zi Chong Kao , in Enova financial’s data competition. Our presentation (code available upon request)

Trip to Tana Toraja

August 06, 2013

During the month of Ramadan, a friend and I decided to hike through parts of Tana Toraja, a popular wilderness destination in Sulaweisi, one of the large islands of Indonesia.

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New Projects

June 15, 2013

Several interesting new projects, including examining cross validation using Amazon’s EC2 for a census data set. The picture is a visual interpreation of the false positive and false negative of logistical regression on earnings > $50K, using census education data.

A Run In The Hills Of Oaxaca

March 15, 2013

I had a truly beautiful run in the hills to the north east of the city. If you want a retreat away from the craziness of the city, check out this route!

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Greetings From Oaxaca

January 15, 2013

Greetings from Oaxaca! The city of Oaxaca is a beautiful place and I can’t wait to explore the countryside. Keep your eyes peeled for further updates and likely some running maps.

Mentioned in Chilean Newpaper El Mercurio

December 12, 2012

The Chilean national newspaper EL Mercurio wrote an interesting article on the experience of the myself and the other international interns at the Chilean Ministry of Finance in the summer of 2012. We were the first batch of international interns as part of the Ministry’s Practicas program, which has now expanded from Harvard and UChicago to several Universities in the US and UK.

Article Link

Trip To Pucon

July 08, 2012

A travel journal of an amazing trip to Pucon

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Learn To Use A Vpn

April 04, 2011

- Using a Virtual Private Network as a UChicago student

UChicago's VPN (Cisco Anyconnect)

What is a virtual private network?

Basically, when you use a VPN (virtual private network), your computer first connects to Uchicago computers. Then, Uchicago computers access the webpage you want and send it to your computer. For the websites you access, it appears as if you are a computer at UChicago. This way, you can access content only available in the US (hulu, Pandora, facebook in China, etc). It also improves security and protects your identity by not revealing your location and IP address.

How to access UChicago's VPN?</br>

- Download the client free at UChicago's VPN (Cisco Anyconnect)

Install the client on your computer

Open the client (called cisco Anyconnect VPN client) on your computer and enter your credentials (cnet ID and password)